In the art of fluid handling couplings which include releasably engageable male and female sections with central axially aligned fluid passages and axially spaced opposing annular sealing faces and/or seats between which annular rubber or rubber-like sealing rings are tightly engaged; the opposing sealing seats and/or faces are commonly defined by axially inwardly or forwardly disposed terminal ends on the male sections and by axially outwardly disposed, radially extending bottoms of sockets entering the rear ends of the female sections and in which the male sections are normally engaged.
A major problem found in couplings of the general character referred to above resides in the tendency for the annular sealing rings, which normally occur at the bottoms of the sockets in female sections, to move out of position and become displaced when the coupling sections are disengaged. More particularly, during and following disengagement of the coupling sections, fluids flowing in and through the coupling sections tend to wash the sealing rings from desired operating position in the sockets of the female sections.
To overcome the above noted problem, it has become common practice in the art of fluid couplings, of the character referred to, to provide radially inwardly opening annular sealing ring retaining grooves in the inner ends of the sockets in the female sections and to increase the outside diametric extent of the sealing rings so that the outer peripheral portions of the rings engage in the grooves, whereby the rings are effectively retained in the sockets in proper operating relationship therewith.
While provision of the above noted sealing ring retaining grooves in the sockets of the female sections of couplings is very effective, establishment of such grooves, which must be cut in the sockets of the female sections by separate and special machining operations is inconvenient, time consuming and results in a material increase in the cost of the resulting couplings.
In practice, the male and female sections of couplings of the character referred to above are preferably mass produced of metal or of plastic resin by die-casting or injection molding techniques. When so producing those coupling sections, the only machining operations which must be performed is the establishment of the sealing ring retaining grooves in the sockets of the female sections. These machine operations, in addition to slowing and limiting production, greatly increase the cost of manufacturing the otherwise inexpensive to produce coupling sections.
As a result of the foregoing, the want, need and/or desirability of the butt seal structure for fluid couplings of the character referred to above, which does not require the machining of special sealing retaining grooves or the like, has long been recognized.